The University of Gothenburg‘s scientific investigation into the Nord Stream leak has returned home. It’s too soon to draw any conclusions from the researchers’ discovery that the methane levels close to the leak were 1,000 times higher than usual. Numerous samples have been returned by the researchers for analysis.
The research vessel Skagerak is back in Gothenburg after five days at sea. The hurriedly planned expedition to the Baltic Sea Nord Stream leaks is now complete, and the researchers are happy with their work.
Given the short amount of time for preparation, “everything has gone incredibly well. The expedition’s coordinator, Katarina Abrahamsson, a marine chemist at the University of Gothenburg, claims that in less than 48 hours, the researchers and equipment she needed were on board.
German scientists assisted
“Since the methane gas leak was found on September 26, methane gas has kept leaking into the water. According to Abrahamsson, in order to measure the effects of this significant discharge and gather crucial data, it was imperative for the researchers to arrive quickly. Over a 54-hour period, the expedition collected 100–200 water samples.
We had 20 different measurement sites with a distance between each of them of roughly 9 to 18 kilometers, which allowed us to map the distribution of the methane in the water. We had researchers and tools from the Alfred Wegener Institute at our disposal. According to Katarina Abrahamsson, they are able to distinguish between pipeline methane and naturally occurring methane.
We discovered that the methane levels in the water samples were up to 1,000 times higher than usual. Additionally, the leak’s methane distribution pattern was convoluted and challenging to comprehend. The fact that the vessel was only permitted to travel in Swedish waters may be the cause of our inability to measure the entire discharge. Simply put, we were unable to contact Denmark in time, claims Katarina Abrahamsson.
Although methane gas is dissolved in water, it changes back to gas when it reaches the surface and is released into the atmosphere. The currents and the moment the leakage stops determine how long the Baltic Sea’s elevated methane levels last.
Unclear effect on marine life
What impact these high methane levels might have on marine life is unknown. For instance, there are bacteria in the water that can grow and multiply by oxidizing methane gas.
According to Carina Bunse, a marine biologist at the University of Gothenburg, “I have filtered water samples during the expedition to see if there has now been a growth of these types of bacteria when there are elevated methane levels in the water.”
Could it affect biological life in the Baltic Sea?
Autumn has arrived, and soon phytoplankton and zooplankton will be in their dormant season. If these methane-eating bacteria expand at the expense of other plankton species, it might have an impact on the local food web. But we are unable to predict the outcome. According to Carina Bunse, we must conduct DNA analyses of the components in the water samples before we can draw any conclusions.
Now that Skagerak is back in Gothenburg, the researchers face an enormous amount of work. The water samples and measurements need to be analyzed and discussed before it is possible to say for sure how the Nord Stream leak emissions will affect marine life in the long run. But new expeditions to the waters east of Bornholm are already in the works for the researchers.
“Now that we have an overview of our findings, we need to summarize them in a preliminary scientific paper. That might, with any luck, be released before the end of the year, according to Katarina Abrahamsson.
